Results 61 to 70 of about 4,289,171 (382)

Simultaneous X-Ray and Infrared Observations of Sagittarius A*'s Variability [PDF]

The Astrophysical Journal, 2019
Abstract Emission from Sagittarius A* is highly variable at both X-ray and infrared (IR) wavelengths. Observations over the last ∼20 yr have revealed X-ray flares that rise above a quiescent thermal background about once per day, while faint X-ray flares from Sgr A* are undetectable below the constant thermal emission.
Daryl Haggard, Daryl Haggard, Frederick K. Baganoff, Mark Morris, Giovanni G. Fazio, E. E. Becklin, J. Neilsen, Joseph L. Hora, Howard A. Smith, Steven P. Willner, G. Witzel, G. Witzel, Patrick J. Lowrance, Sera Markoff, Gabriele Ponti, Hope Boyce   +15 more
openaire   +9 more sources

THE INFRARED ARRAY CAMERA DARK FIELD: FAR-INFRARED TO X-RAY DATA [PDF]

The Astrophysical Journal Supplement Series, 2009
12 pages, ApJS ...
Krick, J. E., Surace, J. A., Thompson, D., Ashby, M. L. N., Hora, J., Gorjian, V., Yan, L., Frayer, D. T., Egami, E., Lacy, M.   +9 more
openaire   +5 more sources

The location of an active nucleus and a shadow of a tidal tail in the ULIRG Mrk 273 [PDF]

, 2011
Analysis of data from the Chandra X-ray Observatory for the double nucleus ULIRG Mrk 273 reveals an absorbed hard X-ray source coincident with the southwest nucleus, implying that this unresolved, near-infrared source is where an active nucleus resides ...
Armus, L., Evans, A. S., Howell, J. H., Iwasawa, K., Komossa, S., Mazzarella, J. M., Petric, A., Sanders, D. B., Surace, J. A., Teng, S. H., U, V., Veilleux, S.   +11 more
core   +2 more sources

Impact of Low-Energy Cosmic Rays on Star Formation [PDF]

, 2020
In recent years, exciting developments have taken place in the identification of the role of cosmic rays in star-forming environments. Observations from radio to infrared wavelengths and theoretical modelling have shown that low-energy cosmic rays ( < 1  
M. Padovani, A. Ivlev, D. Galli, S. Offner, N. Indriolo, D. Rodgers-Lee, A. Marcowith, P. Girichidis, A. Bykov, J. Kruijssen   +9 more
semanticscholar   +1 more source

The Infrared-X-ray continuum correlation in Active Galactic Nuclei

, 2003
The correlation between the soft X-ray and near infrared emission from AGN is analysed using composite models by the code SUMA. We find new evidences for differences in ranges of parameters which characterize the NLR of Seyfert galaxies and LINERs ...
Campos, P. E., Contini, M., Viegas, S. M.   +2 more
core   +2 more sources

The Infrared and X-Ray Continua of Quasars: Is there a Connection ? [PDF]

Symposium - International Astronomical Union, 1989
The first Einstein IPC X-ray spectra of quasars had slopes similar to their infrared spectra (Elvis et al. 1986) suggesting that the infrared and x-ray continua of quasars might be two ends of a single power-law extending over at least 4 decades of the electromagnetic spectrum.
Martin Elvis, Jonathan McDowell, Belinda J. Wilkes   +2 more
openaire   +1 more source

First detection of GeV emission from an ultraluminous infrared galaxy: Arp 220 as seen with the Fermi Large Area Telescope

, 2016
Cosmic rays (CRs) in starburst galaxies produce high energy gamma-rays by colliding with the dense interstellar medium (ISM). Arp 220 is the nearest ultra luminous infrared galaxy (ULIRG) that has star-formation at extreme levels, so it has long been ...
Liu, Ruo-Yu, Peng, Fang-Kun, Tang, Qing-Wen, Wang, Jun-Feng, Wang, Xiang-Yu   +4 more
core   +1 more source

Infrared properties of serendipitous X-ray quasars [PDF]

The Astronomical Journal, 1982
Near-infrared measurements have been obtained of 30 quasars originally found serendipitously as x-ray sources in fields of other objects. The observations show that the infrared characteristics of these quasars do not differ significantly from those of quasars selected by other criteria.
Neugebauer, G., Soifer, B. T., Matthews, K., Margon, B., Chanan, G. A.   +4 more
openaire   +4 more sources

The X-ray emission of local luminous infrared galaxies [PDF]

Astronomy & Astrophysics, 2011
We study the X-ray emission of a representative sample of 27 local luminous infrared galaxies (LIRGs). The median IR luminosity of our sample is log L_IR/L_sun = 11.2, thus the low-luminosity end of the LIRG class is well represented. We used new XMM-Newton data as well as Chandra and XMM-Newton archive data. The soft X-ray (0.5-2 keV) emission of most
Rieke, George, Esquej, Pilar, Ward, Martin, Longinotti, Anna, Jimenez-Bailon, Elena, Colina, Luis, Santos-Lleo, Maria, Alonso-Herrero, Almudena, Pereira-Santaella, Miguel   +8 more
openaire   +3 more sources

Soft gamma-ray constraints on a bright flare from the Galactic Center supermassive black hole

, 2009
Sagittarius A* (Sgr A*) is the supermassive black hole residing at the center of the Milky Way. It has been the main target of an extensive multiwavelength campaign we carried out in April 2007.
A. Goldwurm, Aitken, Baganoff, Baganoff, Baganoff, Balick, Bélanger, Bélanger, Bélanger, Chiar, Clénet, Cotera, Courvoisier, D. Porquet, Degenaar, Do, Doeleman, E. Pantin, Eckart, Eckart, Eckart, Eckart, Eckart, Eisenhauer, F. Melia, F. Yusef-Zadeh, Falanga, Falanga, Ferrando, G. Bélanger, G. Trap, Genzel, Ghez, Ghez, Ghez, Ghez, Gillessen, Goldwurm, Goldwurm, Goldwurm, Goldwurm, Haubois, Herrnstein, Hinton, Hornstein, Jansen, K. Dodds-Eden, Krabbe, Krawczynski, Lagage, Lebrun, Lenzen, Liu, Liu, Liu, Liu, Lund, Lutz, Markoff, Marrone, Melia, Melia, Meyer, Meyer, Meyer, Morris, N. Grosso, P. Ferrando, P.O. Lagage, Pantin, Porquet, Porquet, R. Genzel, R. Terrier, Reid, Reid, Revnivtsev, Revnivtsev, Rousset, Rybicki, S. Gillessen, Schödel, Schödel, Stolovy, Tagger, Telesco, Trippe, Tsuboi, Ubertini, Wang, Westergaard, Winkler, Yuan, Yuan, Yusef-Zadeh, Yusef-Zadeh, Yusef-Zadeh, Zhao, Zhao, Zylka, Čadež   +100 more
core   +3 more sources